Friday, 26 April 2013

Air Pollution in London

When it comes to air pollution most people seem familiar with CO2, acid rain and the like. However there is less appreciation of the significant impact of air pollution much closer to home - the impact of particulates from our roads on Londoners and their lungs.

Given the direct impact on our health, it does not seem to have the level of awareness which it deserves. In addition it is something we can change, both through campaigning and by reducing our personal exposure (avoiding main roads and other pollution hot spots).

Air pollution in London

Air pollution is 50% higher in London than rest of the country, and all of London is a high pollution environment. While much of the pollution we breath in is from main roads locally to where we live and work, this is on top of a high background level in London & northern Europe.

In London the particulate pollution is most dangerous and the impacts on human health are significant and well established. Nitrogen Oxides (NOx) are also high in London, but the impact on human health is not thought to be so significant.

Most air pollution in London comes from transport. 90% of that comes from diesel vehicles which emit approximately 22 times more particulates than the equivalent petrol engine, and 4 times the NOx (however diesels are still encouraged by government).

A reduction of 20-30% in pollution levels is required to meet EU limits (although an improvement, these limits are not safe limits).

Technology upgrade is not delivering significant improvements in this area eg. the Euro standards for cleaner buses have not brought the benefits hoped for.

Health impact:

In central London boroughs 5-7% of all deaths are attributable to air pollution - one of the biggest health problems after smoking.

For particulates, there are no safe limits. PM10s stay in the lungs and therefore reduce lung capacity by 5-17%, permanently.

It affects the vulnerable disproportionately, the poorest being most affected and levels up to 30% higher for non-white British.

Highest exposure is among more vulnerable groups ie the young and the old.

The damage to children reduces lung capacity permanently, reflecting on-going damage to developing lungs, pre-disposing to ill effects later in life.

There is a cognitive decline in children growing up in polluted environments.

There is now data on the cardiovascular effects increasing rate of death.

There is clear evidence that pollution affects birth outcomes.

Higher levels of exercise increase exposure because we breathe in more of the pollutants.

What Can be Done?

Personal mitigation is important and can halve personal intake of pollutants by taking low pollution routes. It is therefore worth drawing maps to tell children which routes to avoid.

Masks don’t work unless they are industrial quality.

Air pollution needs to be tackled through public health, transport and planning. Putney was able to argue in favour of low emission buses in order to protect users of its High Street from the high pollution found there.

The London Plan - developments must be at least air quality neutral and not lead to air quality deterioration. Because London is already failing its polluting targets, development must do all possible to limit pollution.

What needs to be done:

People's awareness of this issue needs to be raised so it gets the attention it deserves.

The worst emitting vehicles on our roads need to be removed, especially older diesel vehicles. Where vehicles are found to be exceeding legal limits they should be taken off the road.

Buses are a significant proportion of the diesel vehicles on our roads and more needs to be done to reduce the particulate pollution from the bus fleet.